Photographic-printing surface and method of making same.



No. 671,882. Paten ted Apr. 9, 19m.

0. ruuon & m. GILLABD.

PHOTOGRAPH"; PRINTING SURFACE AND METHOD OF MAKING-SAME:

(Application filed July 23, 1900.)

(No Model.)

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UNITED STATES PATENT OFFICE".

OTTO FULTON AND MOUNTSTEVEN GILLARD, OF PORT ELIZABETH, CAPE COLONY.

- PHOTOGRAPHlC-PRINTING SURFACE AND METHOD OF MAKING SAME.

SPECIFICATION forming part of Letters Patent No. 671,88 dated April 1901- Application filed July 23, 1900. Serial No. 24,591. (No specimens.)

T0 at whom it may concern:

Be it known that we, OTTO FULTON and MOUNTSTEVEN GILLARD, photographers, subjects of the Queen of Great Britain, residing at Main street, Port Elizabeth, Cape Colony, have invented certain new and useful Improvements in Photographic Printing Surfaces and Methods of Producing the Same, of which the following is a specification.

This invention relates to the production of photographic-printing surfaces in a simple, economical, and expeditious manner without requiring any special ability on the part of the person making and using the same. Furthermore, the printing-surfaces are so formed that a great number of prints or impressions can be obtained therefrom without the aid of any expensive apparatus or machinery upon any desired material and in various colors or tints. Moreover, the said printing-surfaces do not materially deteriorate by remaining out of use for a considerable length of time.

According to our invention we obtain what is known as a collotype printing-surface upon a sheet of celluloid or similar non-flaccid but semirigid waterproof material which is elastic and flexible, so that it can be freely handled like a card and printed from without either being cemented to a mounting-block or stretched at the two ends, as is usually necessary with films that are flaccid. One of the surfaces of the aforesaid sheet must be rough or matte, and to this surface we apply a gelatinous solution, and we dry the coated sheet in such a manner that perfect adhesion of the dried gelatinous film or coating to the said sheet will be insured,as hereinafter explained It is important that the gelatinous solution from which the said film is formed should contain formalin, citric acid, (together or separately,) or some other substance that will tend to harden the film. The said celluloid sheet provided with its gelatinous film is then ready of the sheet is exposed to the light for a short time in order to completely ind urate that portion of the gelatinous film which is in immediate contact with the said sheet. operation the sheet is soaked in water and dried. The surface upon which the photographic picture has been obtained is then treated with a mixture of glycerin, ammonia, and water. After this treatment and when all superfluous moisture has been removed the sheet is ready to receive the printing-ink, which may be applied in any ordinary and well-known manner.

In the drawings accompanying this specification, Figure 1 is an elevation, broken away, of our improved photographic-printing surface; and Fig. 2 is a plan of a mask used in connection therewith.

Referring to the drawings by reference-numerals, 1 indicates a rough or matte sheet of celluloid; 2, the gelatinous film; 3, the sensitized film, and 4 the preservative coating.

The reference-numeral 5 indicates a mask used in the preparation of the printing-surface. This mask may be of any desired form.

The components of the gelatinous film, the sensitized coating, and the preservative will be hereinafter explicitly set forth.

In carrying our invention into practice we take a sheet of celluloid which is rough or matte on one side and thick enough to be rigid in the sense in which a sheet of ordinary thin card is rigid. The thickness of the sheet we prefer to use is about one-hundredth of an inch. Extremely thin celluloid like that used in photographic-roll holders is not satisfactory, neither are sheets the thickness of which reaches one-thirteenth of an inch. It is necessary that the natural translucency of the sheet of celluloid employed shall not be entirely destroyed by the addition or incorporation of pigments. In order to coat the celluloid sheet evenly with the gelatinous film, we proceed as follows, viz: A perfectly flat support preferably consisting of plate-glass is coated with an adhesive solution composed of water, eight (8) ounces; glue, (French,) one After this half (1}) ounce; glycerin, three (3) ounces;

formalin, sixty (60) minims. Such solution is prepared in the following manner: The glue in small pieces is placed in a vessel con- IOO taining the water and allowed to remain therein for some hours, and when the glue is thoroughly softened the vessel is gently warmed until the glue is dissolved. The formalin and glycerin mixed together are then added slowly, the whole being well stirred. The solution is then filtered through a piece of muslin. During the filtering it is desirable to warm the muslin and the vessel intended to contain the adhesive solution. A quantity of this adhesive solution is then poured upon the plate-glass and evenly spread over the entire surface by the aid of a warmed glass rod to form athin coating. The support thus coated is then placed upon a perfectly-level slab and allowed to remain for a few minutes until the adhesive surface has set and cooled. The celluloid sheet is next applied to the adhesive surface of the support and with the rough side upward is slightly pressed down onto the adhesive surface by the hand with the aid of a cloth, great care being taken that no air-bubbles are left between the celluloid sheet and the adhesive surface. When the celluloid sheet has been thus mounted upon the adhesive surface, we coat the said sheet with a gelatinous mixture which is prepared as follows: Gelatin, one hundred and eighty (180) grains; formalin,fifteen (l5) minims; citric acid, five (5) grains; water, five (5) ounces. The gelatin is cut into small pieces, placed in four ounces of the water, and allowed to soak. It is then warmed to a temperature of about 120 Fahrenheit and stirred until dissolved. The vessel containing the mixture should be heated in a water-bath and not directly by a flame. When the gelatin has been completely melted, the formalin and citric acid are mixed with the remaining ounce of water and this liquid is added slowly to the gelatinous mixture and at the same time is well stirred. The. solution is afterward filtered with similar precautions to those already mentioned. We now coat the sheet of celluloid While it is still mounted on the aforesaid support by pouring upon it a sufficient quantity of the solution to cover the sheet with a thin layer, the solution being spread thereon by the aid of a warmed glass rod. A surface eight and one-half inches by eight and one-half inches will ordinarily require about one ounce of the gelatinous solution. The solution is now allowed to set while the celluloid is still on the level adhesive support, and the coating is aft'erward dried at a temperature of about Fahrenheit. Provided that the coating has thoroughly set,there is no objection to placing the support vertically when drying. When 'perfectlydry, the coated celluloid sheet, with its gelatinous film, is removed from the adhesive support bydrawingit olf by one of its corners. It will be found advantageous to place a fresh sheet of celluloid upon the adhesivesupport immediately after the removal after remaining disused for a considerable length of time. The coated celluloid sheet thus obtained is then placed in a sensitizing solution or bath, with the gelatinous film uppermost, this solution being an ordinary bichromate or chromate sensitizing-bath-such as potassium bichromate, one (1) ounce; ammonium hydrate, ten (10) drops; water, forty (40) ounces. In hot weather it may be necessary to cool the sensitizing solution. The sheet is allowed to remain in the sensitizing solution for about two and one-half minutes. It is then removed and placed between folds of damp blotting-paper for the purpose of removing superfluous'moisture, and the sheet is then dried in the dark. When perfectly dry, the sheet is placed, with the photographic negative, in an ordinary printingframe, with the yellow or sensitized side of the celluloid sheet against the negative. Before printing, however, we prefer to place between the glazed opening of the printingframe and the negative a mask, so as to leave a margin around the celluloid sheet of about half an inch, this mask being similar to'the safe edge used by carbon-printers. The margin may be broader, but should not be narrower. We then expose the negativeand the celluloid sheet in a soft light or in the shade until the said celluloid sheet exhibits the picture in all details and graduations. We then remove the negative, still keeping the mask in the frame. We then reverse the celluloid sheet, so that its unsensitized side is toward the glass of the, frame. The sheet is then exposed to the light for about three 1 minutes (or generally about one-fifth of the time of the chief exposure) to harden the gelatinous material which is in immediate contact with the celluloid sheet. We, now remove the celluloid sheet from the printing-frame and place it with the yellow side The quantity of this solution used is sufficient to just cover the picture and a small margin around the same. It is allowed to stand for forty or fifty minutes, according to the softness or hardness of the negative employed. After sponging it and removing all superfluous moisture the. sheet is then ready to receive the printing-ink, which may be the ordinary lithographic or typographic kind mixed with varnish. The ink may be applied to the printing-surface of the celluloid sheet in any ordinary manner. The impressions from the printing-surface can be made on any kind of material and in almost any color and with only a slight pressure obtained by a hand-roller or a letter-press or in any other convenient manner.

From time to time the printing-block should be sponged with a mixture of glycerin and water in about equalproportions.

What we claim, and desire to secure by Letters Patent of the United States, is-

1. The herein-described method of obtaining a photographic-printing surface, consisting in first coating a sheet of suitable material with a hardened gelatinous film having a safe edge, sensitizing the said coating and exposing and then reversing the sheet to allow the light to h arden the whole film excepting the safe edge.

2. The herein-described method of obtaining a photographic-printing surface, consisting in coating a sheet of suitable material with a gelatinous film, sensitizing the said film, masking a .portion of said film while printing to form a safe edge and finally harupon a support having an adhesive surface, coating the outer face of said sheet with a gelatinous film, sensitizing the said film, masking a portion of said film while printing from a negative to form a safe edge, and finally hardening said gelatinous film.

5. The herein-described method of obtaining a photographic-printing surface, consisting of placing a sheet of celluloid upon an adhesive surface, coating the outer face of said sheet with a solution consisting of gelatin, formalin, citric acid and water to form a gelatinous film, sensitizing the said film, masking a portion of said film While printing to form a safe edge, and finally hardening said gelatinous film.

6. A photographic-printingsurface, consisting of a sheet of celluloid having a hardened sensitized film of gelatin, formalin and citric acid with a safe edge.

In testimony whereof We have hereunto set our hands, in presence of two subscribing witnesses, this 18th day of December, 1899.

' OTTO FULTON.

MOUNTSTEVEN GILLARD. Witnesses:

J. COLLINS, FRED C. HARRIS. 

